Routinely collected administrative data were used to estimate diabetes prevalence and utilisation of healthcare services in Counties Manukau, which were then compared with findings for three neighbouring district health boards (DHBs): Northland, Waitemata and Auckland. Reconstructed populations were only 6% lower than census population counts, indicating that the vast majority of the population used health services over the two-year study period (January 2006 to December 2007). The age- and sex-standardised prevalence of diabetes was 7.1% in Counties Manukau and 5.2% in the other three DHBs combined. Prevalence of diabetes was highest amongst Māori (10.6% in women and 12.2% in men) and Pacific peoples (15.0% for women and 13.5% for men). Māori diabetes cases had the highest hospital discharge rate of any ethnic group. Community pharmaceutical prescribing patterns and laboratory test frequency were similar between diabetes cases by ethnicity and deprivation.
